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A day after Beijing's worst air alert of 2015, Xi Jinping spoke of low-carbon development at COP21.

In his opening speech at the climate conference’s leaders event, the Chinese president spoke of international cooperation, low-carbon industrial parks, reducing greenhouse gas emissions, and the country’s 13th five-year plan, which he said would be greener. 

Xi also pitched 100 mitigation climate projects China has planned for other countries, an encouraging commitment, but an interesting one especially in light of the country’s own environmental issues. On November 29, the day before the conference opened, Beijing experienced its highest air alert level for the year, when particulate levels reached ten times the World Health Organization’s guidelines. According to Mashable, at this level of “hazardous” smog, Beijing’s plants must halt or reduce production and large trucks darting between construction sites are barred from the roads.